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玻璃珠载固体超强酸SO_4~(2-)/TiO_2催化合成二甘醇二苯甲酸酯 总被引:2,自引:0,他引:2
以玻璃珠为载体,制备了固体超强酸SO42-/TiO2催化剂,用于催化合成二甘醇二苯甲酸酯(DEDB)。通过实验确定了合成DEDB的适宜工艺条件:回流温度为165~170℃,m(甲苯)/m(二甘醇)=0.5,n(苯甲酸)/n(二甘醇)=2.2,m(催化剂)/m(二甘醇)=0.5,反应时间4 h,在该条件下,酯化率可达99.6%。该催化剂经过10次重复使用,活性每次平均下降2.9%。 相似文献
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磷钨酸铝催化合成二甘醇二苯甲酸酯 总被引:9,自引:0,他引:9
开发了一种用磷钨酸铝催化合成二甘醇二苯甲酸酯 (DEDB)的新方法。研究了催化剂用量、酸 /醇摩尔比、带水剂用量和反应时间对 DEDB收率的影响 ,用正交试验确定了合成 DEDB的最佳工艺条件为 :催化剂∶反应物 =2∶ 1 0 0 (质量分数 ) ,酸∶醇 =2 .1∶ 1 (摩尔比 ) ,带水剂甲苯∶反应物 =1∶ 3.5(质量分数 ) ,反应时间 4h,反应温度为 1 60~ 1 80°C。在此条件下 ,DEDB收率超过95%。催化剂可重复使用多次。 相似文献
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磷钨酸铝催化合成二革醇二苯甲酸酯 总被引:2,自引:0,他引:2
开发了一种用磷钨酸铝催化合成二甘醇二苯甲酸酯(DEDB)的新方法,研究了催化剂用量、酸/醇摩尔比、带水剂用量和反应时间对DEDB收率的影响,用正交试验确定了合成DEDB的最佳工艺条件为:催化剂:反应物=2:100(质量分数),酸:醇=2.1:1(摩尔比),带水剂甲苯:反应物=1:3.5(质量分数),反应时间4h,反应温度为160-180℃。在此条件下,DEDB收率超过95%。催化剂可重复使用多次。 相似文献
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二苯甲酸二甘醇酯(简称DEDB是一种性能优良的增塑剂,其性能稳定,与PVC、聚醋酸乙烯酯、聚乙烯缩了醛等树脂相容性好,增塑效果佳,而且体积电阻率大,耐油污性好.产品成本低,因而具有良好的实用价值。本文介绍利用直接酯化法合成DED,将苯甲酸、二甘醇以一定比例加入到带有搅拌器、分水器及温度计的烧瓶中,用Al2O3作催化剂,在180-210C进行反应,每小时测定酸值一次,反应完毕后进行减压蒸馏,收集0.67kPa下的产品。经多次实验,得到最佳合成工艺条件是:苯甲酸与二甘醇摩尔配比为1:0.8.催化剂用量为苯甲酸量的8%,反应温… 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria. 相似文献
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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed. 相似文献
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。 相似文献
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍. 相似文献
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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many
coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ
within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting
organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled.
An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent
is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible.
UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive
substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using
UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control
over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant
UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely
block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology
of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago,
IL. 相似文献
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Miller DR 《Journal of chemical ecology》2006,32(4):779-794
Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA. 相似文献